I have those wrists on my sin. They are a reward for a quest in Gateway to Khitai. Can't recall the quest and can't check my toon for the item name at the moment, but I'll edit post when I can.
Seeing as you didn't mention the shoulders, I'm hoping that you've managed to find some of that model in purple? I'm pretty sure they don't exist, so I've made do with the grey coloured same model from the item shop.